Four in Yemen, eight in Uganda, one in Kashmir: that's a partial body count of travelers on adventure tours in recent years. The sobering numbers hang like a dark cloud over a booming sector of the tourist industry. So, given the dangers, what is the attraction of these trips? For the stouthearted, the seduction of trekking through the Himalayas, the enticement of Cambodia's temples and the lure of Pakistan's exquisite scenery make treacherous falls, undiscovered land mines and the threat of rebel insurgents acceptable risks. Seeking the thrill of new experiences, growing numbers of travelers are attracted by the challenge of living--if only for a week at a time--on the edge.

Experts say the "adventure tour" market was the fastest growing segment of the U.S. travel industry last year. Increasingly, this business is turning its sights toward Asia. "Almost everyone and his brother has traveled to Europe, or taken a safari in Kenya," says Kim Balazs, director of U.S.-based Asia Tours and Travel. "Asia is the next frontier."

Like any frontier, this one comes with hazards. More than 20% of the countries listed in Fielding's The World's Most Dangerous Places are in Asia, including India, the Philippines and Sri Lanka, all common destinations for Asian explorers. Political volatility and ethnic or religious tensions still make some parts of Asia dicey places to visit. But many travelers simply can't resist the call of adventure. The key, in that case, is to play it safe--and smart. Know what you are getting into. "About 95% of clients come to us with Kipling visions and wanderlust ideas of traveling," says Balazs. "Don't think you're going to Disneyland, because you're not."

Wink Dulles, co-author of The World's Most Dangerous Places--who views his job as "testing the license of a tourist visa"--strongly favors pushing tourism to its limits. Yet Dulles stresses the importance of being well-informed and assuming personal responsibility, as opposed to the "collective-consciousness" approach of many group excursions. "Often the only sources of security are the ground operators, and their No. 1 priority is that the tour goes," he says, adding that a reputable tour agent does not equal a safe trip. Look for yourself before you leap as a group.

If you want the real skinny on places you plan to visit, the confined warnings in guidebooks and the opaque wording of government travel advisories may not be enough. The U.S.-based National Security Institute and The Counter-Terrorism Page can help keep you informed on a country-by-country basis.

Also check out Real World Rescue, which provides up-to-date regional information as well as tips on packing, evacuating and negotiating with locals. For a fee, risk-assessment consultants like Kroll Associates and the Control Risks Group will do the legwork for you.

Warning: this type of travel is not for the uninsured. Balazs recommends finding a reputable insurance company with a history of paying claims. AEA International SOS has packages for individuals that include global medical coverage and emergency assistance. Kroll Associates also offers kidnapping, ransom and extortion policies. Extreme? Perhaps. But better to be safe than sorry.